Liquid-level indicator



' May 24 1927 w. M. PHELPs LIQUID LEVEL INDICATOR Filed April 12, 1922 @Hoz mz 14 Patented May 24, i927.

PATENT CFFECE.

XVILBUR M.-LPHELPS, OF STAUNTON, VIRGINIA.

LIQUID-LEVEL INDICATOR.

pplcation filed April 12, 1922. Serial No.. 551,865,

My invention relates to indicators or gages for showing the levels of liquids in tanks that are more or less removed'from the gage or indicator, and in particular to such devices for showing the level, and therefore the quantity, of gasoline or other fuel in the storage tanks of automobiles. and since my invention has especial reference to this particularvuse, I shall illustrate and describe its embodiment in connection `with an automobile. My object is `to provide apparatus for the purpose stated which is simple of construction and therefore inexpensive to make, whichwill be accurate` and therefore its indications can be relied upon. which will call forI or require little effort or trouble in such 'manipulation as may be necessary. and which, having reference to automobile use, can be installed upon vthe instrument board of the car without being in the way or interferingr with other appliances usually mounted upon vthe instrument My invention consistsinv board of a car. whatever is described by or included within the meaning or scope of the appended claims.

In the accompanyingdrawings:v

Fig. 1 is a. view illustrating ani embodiment of my invention for automobile use, that portion ofthe instrument which is mounted upon the instrument boai'd ofthe ear being shown in perspective, and the gasoline tank in vertical section;

Fig. 2 is aA vertical section through the Vindicator device.V A

Fim ,3 isa l? Iprefer; f

detail view ofthe air pump f Fig. 4 is aview in vertical sectionV with parts in elevation of another form of myf invention. i y

Referring now in detail to what isfshown in the drawings, there are two chambers` oi' receptacles, 10 and 11, respectively, placed one above theother which are-'inthe form of a flat-sided box, each being separately made, or, if preferred, a single box`maybe employed, and provided with a horizontal partition which separates its interior into .two distinct chambers. The lower chamber-in use is intended to be partiallyiilled. say to one third of its height, with a liquid. preferably a light oil,-transforiner oil. for eX- ample, and in communication with the lower` chamber, 10, near its bottom is a gage that may be of. familiar construction consisting of a` glass or` transparent verticaltube, 12,Y

which at its lower end is connected liquidtight with an, elbow, 13; that is connected with the bottom ofthe chamber, 10. and in like manner at its top is connected by an elbow, 14, that extends intothe top of the upper chamber, 11, and within the latter is extended downward nearly to the bottoni of such chamber, 11. Thus the oil or other liquid in the lower chamber, 10, may pass into'the glass tube and its level therein be visible. which level,.as hereinafter explained,

depends upon the level of the Igasoline :inV 'the storage tank, 15, of the car, the interior of which is in communication with the in.- terior of the lower chamber. 10, by suitable tubing or a pipe. 16. there being within the tank. 15, a vertical pipe, 17, that extends from a point near the bottom of the tank where it has a small inlet opening, 18, to oi' through the top of the tank whereat the pipe connection- 16, is made. Within the lower chamber. 10, is a vertically extending pipe. 19,l to whose lower end at or below the bottom ofthe chamber. 10, is connected the pipe, 16. which pipe, 19` Y'extends nearly to the top of the chamber. 1.0, where it has .min the level ofthe liquid in the glass indicator gage, such level risingwith increase' of level ofthe gasoline in the tank, 15. and

falling with the decrease of the level yin the tank, 15. The glass gage lwill have a suitable scale marked unon it whose graduations will correspond with certain levels of gasoline in the tank, 15. For example, one graduation'can denote that the gas tank is full.A another that it is three quarters full.` and so on.` y

Accuracy vof Vreading must take into account,` the effectV of temperature changes on thev apparatus, and in particular upon the column or body of air for transmitting pressure from the gasoline tank to the indicating liquid.' I therefore provide means by which, for each reading, a fresh or new supply "of presaire-transmitting air column introduced.

For this purpose I run a pipe, 21, into the upper chamber, 11, to which is connected an air forcing device such as the pump shown byv which air is pumped into the chamber', 11V, and thence passes through the glass gage, expelling before it the oil in the gage, and into the lower chamber', 10, and from the latter the fresh incoming air passes through the piping into thev gas tank, 15, driving before it the stale air and such gaso- -line as may be in the pipe, 17 in the lgas tank,the air thus expelled into the gas tank being vented therefrom by the vent customarily provided, and thus fresh air slightly above atmospheric pressure may be placed in the piping between gas tank and chamber, 10, so that the gasoline temporarily ez;-

V pelled from the pipe, 17, in the gas tank,

15, may reenter the. pipe to the level in the tank, and moving the air in such pipe, 17, upward, as it enters, will. through the air body or column that reaches to the lower chamber, 10, move the oil therein out into the gage tube and to the level corresponding with the gasoline level in Ythe storage tank, 15. The quantity of air displaced in the pipe, 17, by the gasoline entering therein is transferred to the chamber, 10, and by the increase of air added to the latter the indicating oil is expelled from such chamber to the glass gage and the reverse movement of air takes place whe-n thequantity of gasoline in the fuel tank pipe. 17, diminishes. The hole, 20, in pipe, 19, is small so that there will be no tendency of the air flowing to chamber, 10, from pipe, 19, to cause the oil to flow in spurts or in an agitated manner into the glass gage.

The upper chamber, 11, will receive oil from the glass gage, which foil any reason, in the working of the apparatus may flow therefrom, and such oil as may thus enter chamber, 11, will be forced therefrom back into the glass gage by the action of the air pumping device.

In installing my apparatus on the dash or instrument board, it may be arranged so that only the Iglass gage and operating member of the air pump are visible.

In the use of my apparatus all that is necessary to get an'actuate indication of the quantity of gasoline in the tank is to operate the air pump, and then note the level of the liquid in the gage, which can be done by oneon the car seat.

Any desired form of air forcing device may be used butr I prefer the pump shown best in Fig. 3 which comprises` a cylinder or barrel, '22, placed in a vertical position which is closed at the top, but open at the bottom and near the top opens into the pipe, 21, and has a piston, Q3, which is mounted loosely on the upper end of the piston rod, 24E, between a disk, 26, below the piston and a spider, Q7, above the piston, the space between the disk and spider being greater than the thickness of the piston. The hole, 25, in the piston through which the piston rod passes is sufliciently large to constitute a free passage for air. It will be seen that when the piston rod is moved downward, (which may be done by a handle28, at its lower end), the spider, 27, will move into contact with the top ot the piston and thereby move the pistou downward, and the disk, 26, will be spaced below the-piston, so that air may pass freely upward through the hole, 25, and hence the ydescent of the piston will not result in sucking air out of the chamber, 11, through the hole or pipe, 21.. IIowever, when the piston red, 2l, is moved upward the disk, 26, will engage the underside of the pistou and close the hole, Q5, at thebottom so that air will be forced upward in the barrel by the piston and into the chamber, 11,

through the pipe, 21. 'lhe upward movement of the piston rod is preferably caused by. a coil spring, 29. I'Vhen at its highest point in the barrel, 22, the piston, Q3, is above the pipe,

21. It will be seen that my pump is amostI simple and highly efficientone and 'admin ably fitted foruse as a part of the apparatus.

In Fig. 4l I illustrate an. embodiment of my invention different from that shown in the other figures, it comprising a tank, 1GO, into which extends a pipe, 190, that is conneeted by a pipe, 160,'with the pipe, 17 O ,thatenters the gasolineV tank, 150, and in the tank, 100, is a quantity of oil whose level is determined by the quantity of gasolinein the tank, 150, in a similar manner to the case of the aparatus shown in 1. lVithin the tank, 100, is a cylinder, 120, from the bottom of which a very small pipe, 121, cX- t-ends into the liquid in the tank, '100, bywhich pipe, 121, the liquidmay flow back' and forth between tank, 100, and the cylinder, 120.V The top of the cylinder, 120, is connected by a pipe, 30, with a piston air pump, 31, the piston, 32, of which is mounted o-n a piston rod, 83that` has a handle, 34, below the pump cylinder, and to the piston rod is attached a light rod, 35,7that extends parallel with the"` pump cylinder close to the exterior thereof andat its up-A per end has a pointer or index, 86, that cooperateswith a scale consisting` of graduations or words, ifv desired, that referto the quantity of gasoline inthe tank, 150.v By. means of the pump, 31, the liquid entering the cylinder, 120, from the-tank, 100, to a' level that indicates the level of the gasoline in the tank, 150, may be forced trom the cylinder, 120, and the position of the piston, 32, and t-he index, 36, is determined by the extent of movement ot the piston necessary to expel the liquid from the cylinder, 120, and thus the level of gasoline in the tank, 150, may be indicated. then all the liquid is expelled from the cylinder, 120, that tact is made known to the operator by suitable mea-ns, such, tor example, as 'an electric lamp, 37, mounted in some convenient place which is in a circuit. that includes stationary contact, 38, located about midheig'ht of the cylinder, 120, which at the saine time are touched by a metal plat-e, 39, carried by a float, 40, in the cylinder, '120, and thereby the circuit to the lamp is closed and the light flashes up. 'llhus the instant the light flashes, the operator knows that all the liquid has been expelled from the cylinder, 120, and he stops the expelling"movement vot the pump at that instant, and at that time the pointer, 36, ie at the point on the scale that indicates the level of gasoline in the tank, 150. i

It will be noted that in the construction shown in Fig. 4, the gage device comprises the cylinder, 120, into and out of which the liquid flows, and the index, 36, connected with the pump piston and moving` therewith. y

The employment of separate chambers, l0,

and, l1, is important because otherwise there would be direct communication between the pipe or conduit, 19, and the 'upper end ot' the gage tube in the case ot Figs. 1 and 2' and between the pipe, 190, and the eduction pipe, 30, of the pump in the case oit the construction shown in Fig'. a' so that air pressure transmitted through said pipes from the gasoline container would notproperly inluence the level of the indicating` luid.

Vhat I claim is:

l. The combination with va storage tank or receptacle for a liquid, a liquid holding chamber located away from theV tank, a pipe 1 .leading from a point above the liquid level of said chamber into said tank to the miniinum level to be gauged, a vertical liquid level gauge mounted adjacent said chamber so as to be readily visible and being in communication with such chamber below the level of liquid therein, means to expel the gauge contents into the chamber and the air and other contents from' the pipe between such chamber and said tank, and to place atmospheric air in such pipe, and a second chamber with which the upper end of said gauge communicates, the means ot communication .being` a pipe that terminates in such chamber and spaced troni the bottom there? of, said second chamber being` in communication with said means to expel the gauge contents.

2. rIhe combination with a storage tank for liquid fuel for an automobile, aliquid holding` chamber located away Vfrom the tank at a point on the automobile readily accessible, a pipe leading downward troni within such chamber :trom a point above the liquid level ot said chamber and extended to said tank tothe minimum level to be gauged, a vertical liquid holding gauge mounted adjacentone side of said chamber so as to be readily Visible, the lower end of said gauge-being in communication with the lower Vpart oit said chamber, means mounted adjacent said gauge to expel the gauge contents into said chamber, and the air and other contents tiom the pipe between such` chamber and said tank, and to place atmospheric air vin such pipe, a second chamber situated above the lirst mentioned chamber, a pipe extending from the upper end ot the gauge into said second `chamber and opening into the vlower part thereof, and means establishing communication between said exellino` means and the uaaer )art of saidy p a ii y second ch amber. Y

In testimony whereof I hereunto aiiix my signature.

VYILBUR` M. PHELPS. 

